Demon Wall

The Demon Wall is a surprisingly easy boss enemy to defeat. His whole gimmick is that he slowly comes closer and closer to the party and will eventually crush them. Hence, you have to work somewhat quickly here, but because of his slow speed and your party's power, he'll never even get close. Have Kain Jump or simply physically attack; Cecil and Kain should physically attack each round. Rydia's best bet is to have her use Leviathan, while Rosa heals the party when necessary... otherwise, have her defend. Ultimately, the foe will be no more after three or four rounds if you give him a real pounding. As far as his offensive capabilities, they are minor.